Guest guest Posted November 19, 2002 Report Share Posted November 19, 2002 A direct answer to your confusion follows: " {It is important to base levothyroxine dosage changes on the TSH level and not on the thyroid hormone level. This is because many of the free T4 assays will not appropriately compensate for the high levels of binding proteins in the blood which make the results unreliable.} " (Dr. Ain) Hi dee, What you missed in my reply to Colly was, ( " > > >When I got my thyrogen shots, my TSH went up " ) (Colly) The frame of reference and the context that I was speaking to was that of her having been in the process of a _Thyrogen_ diagnostic process. The Thyrogen process fools the body (Pituitary & Hypothalamus) into producing tsh. So, although the tsh numbers are real.. the body's response as to iodine up-take capability is far from usual as would normally occur if one were really hypo. (thyroxine depleted) My saying that " Low t4 is what causes the true condition/feeling of hyponess, not high tsh numbers. " is in fact, true. Because, in order for tsh to increase.. t4 (in the body's cells) normally, must decrease. As the t4 depletion becomes greater (increases) (deficit climbs) as to remaining quantity.. the observed tsh number will also rise. (increase) And the demand to produce more thyroxine that the Pituitary and Hypothalamus place on an _existing_ and fully-functioning thyroid-gland, also increases. (rising and increasingly higher tsh numbers) <-- But this only happens/occurs/applies _artifically_ when Thyrogen is employed. Thyroxine depletion _does not occur during_ or with the use of Thyrogen, although the tsh numbers would fool you into thinking otherwise, unless one really goes hypo for thyroxine depletion. One must know and understand the specific nature of each of the Thyroid Cancer diagnostic and treatment process and procedures, either going hypo or the Thyrogen method in order to " see " the differences as to what the tsh numbers really represent. ________________________________________________ Regarding: t4 When a patient has titrated their med.'s (thyroxine, t4, Synthroid etc.) to a suppression level of 0.10 or lower, but are experiencing, say, heart palps or other indications of their med. quantity being of too strong a dose (ymmv) and if their free t4 is quite above the normal range.. they have a choice of trying beta-blockers, through which to try and reduce the stress of over-medication, or to reduce their med. amount to a quantity that allows them to feel better. But, as you know.. the risk increases as tsh is allowed to rise much above >0.10 I myself am not interested in what my free t4 is because, I am fortunate in feeling ok while being suppressed within quite a range of <0.10 So even if my t4 is high.. I want to stay on the <0.10 side since I _feel_ ok in so doing. The tsh numbers don't reflect the " how one feels " . But does reflect the degree and magnitude as to the _response_ (demand to make more thyroxine; directed to either the thyroid-gland or in our case, to a nonexistent gland) by the Pituitary & Hypothalamus via rising tsh " numbers " . DR. Ain's reference: " There are also circumstances, such as in thyroid cancer patients who have dysfunctional pituitary glands and are unable to make their own TSH (thyrotropin), in which it is perfectly reasonable for physicians to use Thyrogen® in an unapproved application for radioiodine therapies. On the other hand, patients should not presume that such use is routine nor even optimal for their care. " points out that those for whom no other alternative exists, the fooling of the body's thyroid cells may be of benefit. But going hypo would have to be employed to ensure maximum treatment benefit when using Thyrogen in the case of someone who's Pituitary was non functioning, in order to condition/prepare thyroid cells, whether cancerous or normal, into becoming receptive to/for the up-take of iodine and therefore becoming treatable with RAI on an equal footing as compared with those of us whose tsh will rise upon withdrawal of the thyroid hormone, alone. Dis- continuation of one's med.'s would ensure depletion of thyroxine from existing thyroid cells, cancerous or not, allowing for maximum treatment benefit for those with a normally functioning Pituitary gland. Nick ______________________________________________________________________________ At 11/16/2002 03:35 AM, you wrote: >So...I should be looking at my T4 numbers instead of my TSH? This is >very confusing! > >dee in Austin,TX >TT - 7/02 >dx pap. thyca 7/02 >RAI (29.9 mC) 8/23/02 >last TSH level 17 11/1/02 >currently on synthroid (.200) >follow-up scan planned for 2/03 > ____________________________________________----- Colly wrote: > > >> > >> > >> > >> > At 11/15/2002 08:45 AM, you wrote: >> > >When I got my thyrogen shots, my TSH went up to 109--but I did >not >> > >feel hypo at all.... >> > > >> > >So I guess my question is: are the hypo symptoms the result of >low T4 >> > >or high TSH? >> > > >> > >I know that a high TSH in the absence of T4 is correlated with >hypo- >> > >ness--but with the thyrogen, what role does the TSH play? >> > > >> > >Thanks, >> > > >> > >Colly >> > > Quote Link to comment Share on other sites More sharing options...
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